Portable drilling apparatus including a mechanical,recirculating cooling system

ABSTRACT

A portable drilling apparatus including a recirculating cooling system. A spindle, having a hollow central portion and a gear affixed thereto, is disposed through a housing in which a pair of idler gears are rotatably mounted. The idler gears mesh with the drive gear, and when the spindle is rotated, cooling liquid is drawn in through inlet passages by the suction created by the meshing gears. The liquid is pumped into the hollow spindle, and through a pair of longitudinally extending parallel apertures provided in a drill bit secured in the end of the spindle. The fluid is caught in a sump disposed below the material being drilled, and is pumped through a filter and hose coupling back to the housing by the gears.

United States Patent Ganser et al.

[ Dec. 25, 1973 PORTABLE DRILLING APPARATUS INCLUDING A MECHANICAL,

RECIRCULATING COOLING SYSTEM Inventors: Herman Ganser, 8353 264th St.,

Floral Park; Alfred Ganser, 86-09 208th St., Queens Village, both of NY.

Filed: July 31, 1972 Appl. No.: 276,476

Int. Cl B23b 51/06, B23b 31/02 Field of Search 408/56, 57, 59; 173/75; 10/106; 279/20; 418/196 References Cited UNITED STATES PATENTS 11/1936 Hill et al 408/57 Primary Examin,erFrancis S. l-lusar Att0rneyAllison C. Collard 5 7 ABSTRACT A portable drilling apparatus including a recirculating cooling system. A spindle, having a hollow central portion and a gear afiixed thereto, is disposed through a housing in which a pair of idler gears are rotatably mounted. The idler gears mesh with the drive gear, and when the spindle is rotated, cooling liquid is drawn in through inlet passages by the suction created by the meshing gears. The liquid is pumped into the hollow spindle, and through a pair of longitudinally extending parallel apertures provided in a drill bit secured in the end of the spindle. The fluid is caught in a sump disposed below the material being drilled, and is pumped through a filter and hose coupling back to the housing by the gears.

7 Claims, 3 Drawing Figures PORTABLE DRILLING APPARATUS HNCLUDING A MECHANICAL, RECKRCULATING COOLING SYSTEM The present invention relates to drilling machines, and in particular to a portable drilling apparatus which includes a mechanical, recirculating cooling system.

Deep drilling machines which utilize elongated drills having hollow chambers for receiving oil forced thereinto under pressure are known in the prior art. Such drills are necessary to remove the chips cut by the drill bit during drilling. These drills, however, utilize liquid pumping systems which require an expensive oil pump attached to the drill press, and a separate pump motor to drive the oil pump. The oil pump and associated apparatus is also integrally constructed with the drill press, and it is difficult to repair or remove the pumping system parts from the drill when required.

Accordingly, the present invention provides a mechanically cooled drilling apparatus for a drilling machine, which includes a recirculating cooling system, and is unitized and portable so as to be removable from the drive mechanism of the drilling machine. The drilling apparatus comprises a housing, a rotatable spindle disposed through the housing perpendicular thereto, and having a tapered end portion at one end thereof for engaging the drive mechanism of the drilling machine, and a drill bit secured in the other end thereof for drilling material. The drill bit has a pair of longitudinally extending parallel apertures disposed therethrough which open to both ends of the drill bit. The spindle includes a hollow portion disposed between its tapered end and the drill bit, into which one end of the drill bit extends, and a plurality of radially outwardly disposed apertures positioned at one end of the hollow portion adjacent the tapered end of the spindle which open to the hollow portion. A drive gear is disposed on the spindle within the housing in a recess provided therein, and engages two idler gears disposed on opposite sides of the drive gear in the recess. A plurality of longitudinal, horizontal inlet passages are provided in the housing and communicate with the recess in which the gears are disposed. Cooling and lubrication fluid is circulated through these horizontal passages to the recess in which the gears are disposed. The gears form a mechanical gear pump which pumps cooling liquid through a plurality of outlet passages to the radially outwardly extending apertures, into the hollow portion of the spindle, and through the parallel apertures provided in the drill bit. A sump is disposed below the material being drilled to catch the cooling liquid forced from the drill bit. The sump is coupled to the housing inlet passages, and the liquid is recirculated from the sump back to the housing and to the drill bit.

It is, therefore, an object of the present invention to provide a drilling apparatus for a drilling machine which includes a mechanical recirculating cooling and lubricating system for cooling and lubricating the drill bit and removing drill chips.

It is another object of the present invention to provide a portable drilling apparatus for a drilling machine which includes a mechanical cooling and lubricating system and is easily removeable from the drilling machine drive mechanism, and which is secured on the machine only by the drive mechanism thereof.

It is still a further object of the present invention to provide a drilling apparatus for a drilling machine which is simple in design, easy to manufacture, and efficient and reliable in operation.

Other objects and features of the present invention will-become apparent from the following detailed description taken in connection with the accompanying drawings which disclose one embodiment of the invention. It is to be understood, however, that the drawings are designed for the purposes of illustration only, and are not intended as a definition of the limits and scope of the invention.

In the drawings, wherein similar reference numerals denote similar elements throughout the several views:

FIG. 1 is a side view of a drilling apparatus constructed in accordance with the present invention, shown during use in a drilling machine;

FIG. 2 is a top cross-sectional view of the drilling apparatus, taken along section 22 of FIG. 1; and

FlG. 3 is a front cross-sectional view of the drilling apparatus taken along section 33 of FIG. 2.

Referring to the drawings, there is shown a drilling apparatus, generally denoted as 10, which comprises a housing 11 through which a cylindrical spindle 12 is disposed perpendicular to the top surface of the housing. The spindle includes a tapered end portion 13, which is disposed in the drive mechanism of the drilling machine 14, and is secured in housing 11 by a pair of O-rings 15 which are disposed in grooves 16 and 17 provided in the exterior surface of the spindle and in the housing. Retainer ring 18 is disposed over the lower end of the spindle to additionally secure the spindle in the housing. The spindle has a threaded end portion 19 on which a lock collar 20 is threadably engaged for securing drill bit 21 in a drill chuck 22. The spindle is provided with a hollow portion 23 between its tapered end and the drill chuck, into which one end of drill bit 21 extends so that a pair of longitudinally extending parallel apertures 24 provided in drill bit 21 open into the hollow portion. An O-ring seal 36 is disposed in collar 20 to provide a liquid seal between the collar and drill bit 21. At the top of the recess, adjacent tapered end portion 13, a plurality of circular, radially outwardly extending apertures 25 are disposed in the spindle. These apertures open into hollow portion 23 provided in spindle 12.

A drive gear 26 is disposed on the spindle in the housing in a recess 27. Idler gears 28 are rotatably mounted in recess 27, and engage drive gear 26. The idler gears are disposed on vertical shafts which are supported on needle bearings 37 in recess 27. The shape of the recess conforms to the exterior shape of the gears, and the dimensions of recess 27 are such that it is slightly larger than the overall dimensions of the idler and drive gears in the illustrated arrangement. A pair of outlet passageways 29 extend upwardly from recess 27 from the points of engagement of gears 28 with drive gear 26 to a point adjacent apertures 25 in spindle 12. At least two inlet passages 30 are disposed in the housing and are coupled to a main inlet passage 31. Cooling liquid is admitted through a pipe fitting 32 into inlet passages 31 and 30, as shown in FIG. 2. The idler gear and drive gears form a gear pump when the spindle rotates, and liquid is pumped from inlet passages 30 to passageways 29, apertures 25, and hollow portion 23. The cooling liquid in hollow portion 23 is forced through apertures 24 in the drill bit, and is caught in a sump 32 which is coupled by a flexible hose coupling 33 to pipe fitting 32. A filter 34 filters the drill chips cut from the material from cooling liquid 35.

A safety valve is provided in housing 11 between outlet 29 and inlet 30 to prevent excessive pressure buildup in the housing. The safety valve comprises a cylindrical channel 37 coupled at one end to inlet 30 and at the other end to outlet 29. The end of channel 37 coupled to outlet 29 is tapered inwardly. A spherical ball 38 is disposed in channel 37, and engages the interior walls thereof under pressure from a spring 39 disposed in the channel so as to seal channel 37 and prevent admittance of cooling liquid from outlet 29. A bolt 41 is threadably engaged in aperture 40, and secures spring 39 and ball 38 in channel 37. When the pressure at outlet 29 exceeds the biasing force of spring 39, ball 30 is moved rearwardly in channel 37 to admit liquid to channel 37 and back into inlet 30. This pressure release prevents any damage to the apparatus during operation.

During operation of the drill, spindle 12 is rotated by the drive mechanism of the drilling machine, and rotates drive gear 26 and idler gears 28. The gears create a suction and cooling liquid 35 is drawn between the meshed teeth of the gears into recess 27 where it lubricates the gears. The liquid is then pumped upwardly through passageways 29 to the rotating circular apertures 25 provided in the spindle, from the passageways through the apertures into hollow portion 23, and downwardly through longitudinal apertures 24 provided in drill bit 21. As the drill rotates in the material, drill chips are forced upward in the flutes of the drill bit by the cooling liquid, which drains off into sump 32 as it flows out of the drilling hole over the material being drilled. The suction created by the gears then draws the liquid through filter 34, which filters out the chips, and hose 33 into inlet passage 31 in the housing.

The spindle is secured on the drilling machine only by tapered end portion 13 which is secured in the drive mechanism of the machine. No other fastening means is required, since idler gears 28, which are disposed on opposite sides of drive gear 26, produce opposing torque forces which counterbalance each other, and prevent housing 11 from spinning around spindle 12, as would occur if a conventional two-gear pump were used. This feature of the invention totally eliminates the need for any fastening means to secure housing 11 during drilling.

The drilling apparatus and recirculating cooling system may be used with any type of conventional drilling machine as well as other machines, such as a lathe, since the apparatus is unitized and portable. The tapered end of spindle 12 is merely secured in the drive mechanism of the machine to begin drilling. Any suitable conventional construction materials may be used to build the drilling apparatus of the present invention. However, housing 11 is preferably constructed of aluminum in order to provide a lightweight portable unit which may be easily removed from the machine. Any suitable lubrication and cooling medium, such as oil, may be utilized as the cooling liquid in the drilling apparatus.

While only one embodiment of the invention has been shown and described, it will be obvious to those persons skilled in the art that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.

We claim:

1. A portable liquid cooling apparatus for a drilling machine, comprising:

a housing having a recess disposed therein and inlet and outlet passages opening into said recess;

a rotatable spindle disposed through said housing in said recess and having a hollow portion open at one end thereof communicative with said outlet passages;

a drive gear disposed on said spindle within the recess in said housing; and

a plurality of idling gears rotatably mounted in said recess and engaging said drive gear to form a gear pump, said inlet passages in said housing opening into the area where said drive gear and said idler gears mesh so as to force cool liquid through said outlet passages into the hollow portion of said spindle, said spindle further comprising a drill chuck disposed in the end of said spindle for receiving a drill bit, and a rotatable collar threadably disposed over the end of said spindle over said drill chuck for securing the drill bit in said drill and said spindie.

2. The apparatus as recited in claim 1, wherein said plurality of idler gears comprise a pair of substantially identical gears engaging said drive gear on opposite sides thereof to produce counter balancing forces on said housing during rotation of said spindle so that said housing remains substantially stationary during the drilling operation.

3. The apparatus as recited in claim 1, wherein said spindle comprises a plurality of radially disposed apertures opening into said hollow portion and communicative with said outlet passages.

4. The apparatus as recited in claim 1, further comprising a sump, disposed below said housing, and coupled to said inlet passages in said housing, for receiving the cooling liquid pumped from said spindle, means for circulating the cooling liquid back to said housing, for filtering said liquid during the drilling operation.

5. The apparatus as recited in claim 4, wherein said circulating means comprises a flexible hose coupling, coupled at one end to said sump and to said inlet passages of said housing at the other end thereof, for recirculating cooling liquid from said sump back to said housing.

6. The apparatus as recited in claim 5, wherein said spindle further comprises a tapered end portion opposite said hollow end portion and extending above said housing, or engaging the drive mechanism of a drilling machine for rotating said spindle.

7. The apparatus as recited in claim 1, additionally comprising at least one passageway connecting said inlet with said outlet, and at least one check valve closing said passageway so that liquid from said outlet will flow into said inlet when the pressure in said inlet reaches a predetermined level. 

1. A portable liquid cooling apparatus for a drilling machine, comprising: a housing having a recess disposed therein and inlet and outlet passages opening into said recess; a rotatable spindle disposed through said housing in said recess and having a hollow portion open at one end thereof communicative with said outlet passages; a drive gear disposed on said spindle within the recess in said housing; and a plurality of idling gears rotatably mounted in said recess and engaging said drive gear to form a gear pump, said inlet passages in said housing opening into the area where said drive gear and said idler gears mesh so as to force cool liquid through said outlet passages into the hollow portion of said spindle, said spindle further comprising a drill chuck disposed in the end of said spindle for receiving a drill bit, and a rotatable collar threadably disposed over the end of said spindle over said drill chuck for securing the drill bit in said drill and said spindle.
 2. The apparatus as recited in claim 1, wherein said plurality of idler gears comprise a pair of substantially identical gears engaging said drive gear on opposite sides thereof to produce counter balancing forces on said housing during rotation of said spindle so that said housing remains substantially stationary during the drilling operation.
 3. The apparatus as recited in claim 1, wherein said spindle comprises a plurality of radially disposed apertures opening into said hollow portion and communicative with said outlet passages.
 4. The apparatus as recited in claim 1, further comprising a sump, disposed below said housing, and coupled to said inlet passages in said housing, for receiving the cooling liquid pumped from said spindle, means for circulating the cooling liquid back to said housing, for filtering said liquid during the drilling operation.
 5. The apparatus as recited in claim 4, wherein said circulating means comprises a flexible hose coupling, coupled at one end to said sump and to said inlet passages of said housing at the other end thereof, for recirculating cooling liquid from said sump back to said housing.
 6. The apparatus as recited in claim 5, wherein said spindle further comprises a tapered end portion opposite said hollow end portion and extending above said housing, or engaging the drive mechanism of a drilling machine for rotating said spindle.
 7. The apparatus as recited in claim 1, additionally comprising at least one passageway connecting said inlet with said outlet, and at least one check valve closing said passageway so that liquid from said outlet will flow into said inlet when the pressure in said inlet reaches a predetermined level. 